Answer:
200 litres
Step-by-step explanation:
let g be gasoline used, d the distance travelled and s the speed, then the equation relating the quantities is
g = kd[tex]\sqrt{s}[/tex] ← k is the constant of variation
To find k use g = 25, d = 100 and s = 100, then
25 = k × 100 × [tex]\sqrt{100}[/tex] = k × 100 × 10 = 1000k ( divide both sides by 1000 )
0.025 = k
g = 0.025d[tex]\sqrt{s}[/tex] ← equation of variation
When d = 1000 and s = 64, then
g = 0.025 × 1000 × [tex]\sqrt{64}[/tex] = 0.025 × 1000 × 8 = 200
